POEMS syndrome: clinical, pathological and immunological study of a case.

A young Italian woman with a POEMS syndrome is described. The patient had a plasma cell dyscrasia without clinical or laboratory evidence of multiple myeloma. The phenotypic analysis of bone marrow cells and peripheral blood lymphocytes revealed a normal pattern. The immunological study of CSF showed high levels of interleukin-6, whereas this cytokine was not detectable in the serum. Electrophysiological studies and sural nerve biopsy showed a mixed, demyelinating-axonal sensorimotor neuropathy with marked loss of large myelinated fibres. Long-term treatment with prednisone gave some clinical improvement.